Kidneywood

Eysenhardtia orthocarpa

kidneywood blooming at Academy Village

About the Plant

Kidneywood is native to southeastern Arizona, a large shrub or multistemmed tree that will grow to 15-20 feet, tall enough to provide shade for a patio or even the side of a house. This tree drops its leaves in winter. In April, the leaves return and the elongated clusters of white flowers appear. Flowering will continue off and on all summer.

If you want to grow kidneywood as a tree rather than a shrub, select a tree-form at the nursery. This tree is drought-tolerant but will be fuller with some irrigation. Protect the bark of newly-planted trees from hungry rabbits with a circle of chicken wire. The fruit is small but this plant has been known to reseed. If you grow it, look for new plants nearby.

Notes: kidneywood is fairly new to the nursery trade and owes its introduction to the Desert Legume Program at University of Arizona.

Wildlife value: bees, butterflies and other insects, and hummingbirds feed on the flowers. The leaves are food for the larvae of two native Arizona butterflies - gray hairstreak and Arizona mottled skipper.

More Information

Weekly Plant on kidneywood

Map of distribution in US (yellow means plant is native but rare)

Technical botanical description from SEINet

In books:

Trees and Shrubs for the Southwest by Mary Irish, page 197.

ID Characteristics 

This plant is in the Fabaceae - the legume (pea and bean) family.
Kidneywood is a large shrub or multistemmed tree. It can grow to 20 feet high and 12 feet wide. It has a bit of a tufted appearance since leaves tend to grow together in groups.
The bark of young stems is a medium gray with many white lenticels. There are no thorns or spines. As the bark ages it first roughens, then begins to shred in vertical strips, pulling away from the trunk just slightly.
The alternate leaves of kidneywood are pinnately compound with many small leaflets. They are 4+ inches long. They can be drought deciduous. In the Tucson area, they are almost always cold deciduous, typically reappearing in late April.
The white flowers are held on 3 inch elongated clusters. Each flower is about 1/4 inch x 1/4 inch. The five petals form a short tube, then flair out. The flowers are almost, but not quite, regular (actinomorphic). They have a slight vanilla fragrance.
If pollinated, each flower forms a single-seeded pod, thin and about 1/2 inch long, initially green, then turning dark. The mature fruit can stay on the tree into spring.